Vehicle line-locking brake system and method

Abstract

A line-locking brake system consists of a brake pressure generator which, in conjunction with a brake fluid solenoid isolates the front brake circuit from the master cylinder while maintaining a precise brake pressure in the front brake hydraulic system. The brake pressure generator consists of a pressure amplifier having a high pressure chamber located in the flow path from the master cylinder to the front brake cylinders and a low pressure chamber in fluid communication with a regulated gas pressure source. When activated, the brake pressure generator applies a pressure to the front brake circuit that is directly proportional to the pressure of the regulated gas and therefore is precisely controllable irrespective of wear on parts, driver fatigue or other variables.

What is claimed is: 
     
       1. A line locking apparatus for locking the hydraulic front wheel brake system of a vehicle, the hydraulic front wheel brake system comprising a brake master cylinder, a plurality of front brake pistons and hydraulic tubing attached between the brake master cylinder and the plurality of front brake pistons, the line locking apparatus comprising:
 a brake fluid solenoid operatively disposed between the brake master cylinder and the plurality of front brake pistons, the brake fluid solenoid moveable between an open and a closed position for isolating the plurality of front brake pistons from the brake master cylinder; 
 a brake pressure generator operatively disposed between the brake fluid solenoid and the plurality of front brake pistons, the brake pressure generator moveable between two selectable states, wherein in the first selectable state, the brake pressure generator applies no hydraulic pressure to the plurality of front brake pistons and in the second selectable state, the brake pressure generator applies a predetermined hydraulic pressure to the plurality of front brake pistons, the brake pressure generator comprising a hydraulic amplifier having a high pressure chamber and a low pressure chamber, the high pressure chamber being operatively disposed between the brake fluid solenoid and the plurality of front brake pistons, the low pressure chamber having an inlet port for receiving a flow of pressurized fluid to create pressure in the low pressure chamber, the low pressure chamber having a plurality of exhaust ports for discharging the pressure in the low pressure chamber, the plurality of exhaust ports being configured so that the collective cross sectional flow area of the plurality of exhaust ports are greater than the flow area of the inlet port; and 
 a driver interface enabling the driver to selectively move the brake fluid solenoid from the open position to the closed position and move the brake pressure generator from the first state to the second state, whereby the hydraulic front wheel brake system is isolated from the brake master cylinder and a predetermined hydraulic pressure is applied to the hydraulic front wheel brake system, the driver interface further enabling the driver to selectively move the brake pressure generator from the second state to the first state, whereby the pressure in the low pressure chamber is exhausted rapidly through the at least one exhaust port and the predetermined hydraulic pressure is rapidly released from the front wheel brake system. 
 
     
     
       2. The line locking apparatus of  claim 1 , wherein:
 the hydraulic amplifier includes a dual-diameter piston, the-dual diameter piston having a large surface disposed in the low pressure chamber and a small surface disposed in the high pressure chamber. 
 
     
     
       3. The line locking apparatus of  claim 1 , further comprising:
 a pressure vessel for supplying a source of compressed gas; 
 a pressure regulator operatively attached between the pressure vessel and the inlet port of the hydraulic amplifier for supplying a source of regulated fluid pressure to the low pressure chamber of the hydraulic amplifier. 
 
     
     
       4. The line locking apparatus of  claim 3 , further comprising:
 an air solenoid operatively disposed between the pressure vessel and the inlet port of the hydraulic amplifier, the air solenoid moveable between an open and closed position for selectively providing gas pressure to the low pressure chamber of the hydraulic amplifier. 
 
     
     
       5. The line locking apparatus of  claim 4 , wherein:
 the hydraulic amplifier has an amplification ratio of 300-500%.